Keep sayin it, joe, till the OP acknowledges it. The rest of us are you're reinforcements. 'Course the OP may have done blowed his self up already.
I wasn't even thinkin about the power going out into the grid, but think of the pride you'd feel from sending your electritricity to another state. Who would have thunk that just by plugging a generator into an outlet you'd have to notify the local distribution authorities that you were a producer? I was mostly thinkin about the other outlets he might be powering up without knowing it, screwiness of the various grounding and neutral lines, and the concerns arising from having a male plug on the generator, at least I think that was what he wanted to do. Or perhaps the ever popular male-male jumper. I did use one of those in a Scout Camping eguipment/ chuck wagon trailer once, but we were dealing with 12 volts from battery for lighting.
I've never been involved in permanently installing a large back up generator. One thing I'd worry about with an automatic system is storm damaging some wiring in home, perhaps along with a gas leak. Authorities do warn us when power and gas go out to turn mains for both off so there are no surprizes when they come back on, especially if you are not home when they do.
I have built a few shelters for smaller ones for essential power, refrigerator, freezer, few lights, TV. We ran a short line to switch box near reefer to keep extension cords to minimum. Switched outlets to cut off big drains to run another one. Reefer off a few while well pump, micro wave, or small space heater or window AC is on etc.
I reckon its an individual decision how big a generator to buy, whole house or bare minimum for freezer and a light bulb, . Cost of generator compared to how long you may have to use it. Folks got along without electricity longer than we've come to rely on it. Of course some folks want it all and right now! Like that mayor who damned the Red Cross 'cause they weren't right there and fixed his town good as new within an hour of the storms passing.
Measure twice, cut once.
Look at the nail, not the hammer. Watch the fence, not the blade.
If you hook your thumb over your belt you won't hit it with the hammer or leave it layin on the saw table.